JP2004043677A - Plasticizer for polyester resin - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a plasticizer for polyester resins which can flexibilize an amorphous polyester resin without detriment to its transparency and to provide an amorphous polyester resin composition excellent in flexibility, transparency, and heat resistance. <P>SOLUTION: The plasticizer contains an ester of the following components (a) with the following component (b). Component (a) is a hydroxyl-terminated polycarbonate diol containing repeating structural units [hereinbelow referred to as structural units (I)] represented by general formula (I) (wherein n is an integer of 2-6). Component (b) is at least one member selected from among an aromatic monocarboxylic acid represented by general formula (II) (wherein X is a hydrogen atom, a hydroxy group, a 1-22C straight chain or branched alkyl group, an alkenyl or alkoxy group, or a halogen atom; and m is an integer of 1-5, provided that mXs may be the same or different from each other), a fused polycyclic aromatic monocarboxylic acid, an alicyclic monocarboxylic acid, a hydroxy fused polycyclic aromatic monocarboxylic acid having at least one hydroxy group in the molecule, a hydroxy alicyclic monocarboxylic acid, and anhydrides or 1-3C lower alkyl esters of these carboxylic acids. <P>COPYRIGHT: (C)2004,JPO

Description

【０００７】
（式中、ｎは２〜６の整数を示す。）
で表される繰り返し構造単位（以下構造単位（Ｉ）という）を含み、両末端が水酸基であるポリカーボネートジオール。
（ｂ）一般式（ＩＩ）
【０００８】
【化４】

【０００９】
（式中、Ｘは水素原子、水酸基、炭素数１〜２２の直鎖若しくは分岐鎖アルキル基、アルケニル基又はアルコキシ基、あるいはハロゲン原子を示し、ｍは１〜５の整数を示し、ｍ個のＸは同一でも異なっていてもよい。）
で表される芳香族モノカルボン酸、縮合多環式芳香族モノカルボン酸、脂環族モノカルボン酸、１分子中に１個以上の水酸基を有するヒドロキシ縮合多環式芳香族モノカルボン酸、ヒドロキシ脂環族モノカルボン酸又はこれらカルボン酸の無水物あるいは炭素数１〜３の低級アルキルエステルから選ばれる少なくとも１種。
【００１０】
【発明の実施の形態】
［可塑剤］
本発明の可塑剤は、（ａ）成分と（ｂ）成分とのエステル（以下本発明のエステルという）を含有する。本発明のエステルを構成する（ａ）成分としては、ｎが２〜６から選ばれる１種の構造単位（Ｉ）、好ましくはｎが４〜６から選ばれる１種の構造単位（Ｉ）を含む化合物、ｎが２〜６から選ばれる２種の構造単位（Ｉ）、好ましくはｎ＝５と６、又はｎ＝４と６の構造単位（Ｉ）を含む化合物、ｎが２〜６から選ばれる３種の構造単位（Ｉ）、好ましくはｎ＝４、５及び６の３種の構造単位（Ｉ）を含む化合物等が挙げられる。これらの中では、非晶性ポリエステル樹脂との相溶性と柔軟性付与の観点から、ｎ＝４〜６の構造単位（Ｉ）を含むものが好ましく、異なる整数ｎを有する２種以上の構造単位（Ｉ）を含むものが更に好ましく、ｎ＝４〜６から選ばれる２種以上の構造単位（Ｉ）を含むものが特に好ましい。また、異なる整数ｎを有する２種以上の構造単位（Ｉ）を含む場合、これらはランダム状に結合していても、あるいはブロック状に結合していてもよい。更に、非晶性ポリエステル樹脂との相溶性の観点から、１種の構造単位（Ｉ）のモル分率は８５％以下が好ましく、更に７０％以下が好ましく、特に６０％以下が好ましい。
【００１１】
本発明のエステルを構成する（ａ）成分の平均分子量は、非晶性ポリエステル樹脂との相溶性の観点から４００〜３０００が好ましく、更に６００〜２５００が好ましく、特に８００〜２０００が好ましい。尚、この平均分子量は、（ａ）成分の水酸基価から求めた数平均分子量である。
【００１２】
本発明のエステルを構成する（ｂ）成分において、一般式（ＩＩ）で表される芳香族モノカルボン酸としては、安息香酸、置換基として水酸基、炭素数１〜２２、好ましくは１〜１２のアルキル基、アルケニル基基又はアルコキシ基、あるいは塩素原子、臭素原子等のハロゲン原子を１〜５個、好ましくは１〜２個有する安息香酸が挙げられる。具体的には安息香酸、サリチル酸、ｐ−ヒドロキシ安息香酸、メチル安息香酸、ｎ−デシル安息香酸、イソデシル安息香酸、２−ヒドロキシ−３−メチル安息香酸、２−ヒドロキシ−５−メチル安息香酸、２，４−ジヒドロキシ安息香酸、２，３−ジヒドロキシ安息香酸、３，４，５−トリヒドロキシ安息香酸、４−ヒドロキシ−３−メトキシ安息香酸等が挙げられる。縮合多環式芳香族モノカルボン酸としては、α−ナフタレンカルボン酸、β−ナフタレンカルボン酸等が挙げられる。脂環族モノカルボン酸としては、シクロヘキサンカルボン酸、シクロペンタンカルボン酸、シクロヘプタンカルボン酸等が挙げられる。１分子中に１個以上の水酸基を有するヒドロキシ縮合多環式芳香族モノカルボン酸としては、３−ヒドロキシ−２−ナフトエ酸、１−ヒドロキシ−２−ナフトエ酸、１，４−ジヒドロキシ−２−ナフトエ酸等が挙げられる。ヒドロキシ脂環族モノカルボン酸としては、４−ヒドロキシシクロヘキサン酸等が挙げられる。
【００１３】
これら（ｂ）成分の中では、安息香酸、サリチル酸、ｐ−ヒドロキシ安息香酸又はそれらの炭素数１〜３の低級アルキルエステルが好ましく、特に耐熱性の観点から、サリチル酸が好ましい。
【００１４】
本発明のエステルは上記のような（ａ）成分と（ｂ）成分とのエステル化反応又はエステル交換反応によって得られるが、具体的な製造法としては、例えば、（ａ）成分と（ｂ）成分とを、酸化ジブチルスズ等の有機金属系触媒を、（ａ）成分と（ｂ）成分の合計仕込量に対し０．０１〜０．５重量％使用し、１９０〜２３０℃でエステル化反応を行う方法、過剰の一般式（ＩＩ）で表される芳香族モノカルボン酸のメチルエステルである（ｂ）成分と（ａ）成分とを、酸化ジブチルスズ等の有機金属系触媒を、（ａ）成分と（ｂ）成分の合計仕込量に対し０．０１〜０．５０重量％使用し、１７０〜２３０℃でエステル交換反応を行い、反応後に水蒸気蒸留を行って過剰の（ｂ）成分を留去する方法等が挙げられる。エステルは部分エステルでも全エステルでも良く、樹脂との相溶性及び耐熱性の観点から全エステルが好ましい。
【００１５】
本発明のエステルは、樹脂との相溶性及び耐熱性の観点から、（ａ）成分がｎ＝４〜６から選ばれる２種以上の構造単位（Ｉ）を含むポリカーボネートジオールであり、（ｂ）成分が安息香酸、サリチル酸、ｐ−ヒドロキシ安息香酸である組み合わせから得られるエステルが好ましく、特に（ａ）成分がｎ＝４〜６から選ばれる２種以上の構造単位（Ｉ）を含み、１種の構造単位のモル分率が８５％以下のポリカーボネートジオールであり、（ｂ）成分がサリチル酸である組み合わせから得られるエステルが好ましい。
【００１６】
本発明の可塑剤は、本発明のエステル以外に、本発明のエステル製造における未反応分である（ａ）成分や（ｂ）成分、あるいは本発明のエステル以外のエステル等を含有することができる。
【００１７】
本発明のエステル以外のエステルとしては、ジプロピレングリコールジベンゾエート、エチレングリコールジベンゾエート、ネオペンチルグリコールジベンゾエート、ポリオキシエチレンメチルエーテルアジピン酸ジエステル等が挙げられる。
【００１８】
本発明の可塑剤中の、本発明のエステルの含有量は、本発明の目的を達成する観点から、好ましくは５０重量％以上であり、より好ましくは７０重量％以上であり、さらに好ましくは９０重量％以上である。
【００１９】
［非晶性ポリエステル樹脂］
本発明において「非晶性ポリエステル樹脂」とは、下記で定義される半結晶化時間が５分以上のポリエステル樹脂をいう。
【００２０】
＜半結晶化時間＞
まずアルミニウムパンにポリエステル樹脂を１５ｍｇ秤取り、示差走査熱量測定（ＤＳＣ）装置を使用し、３００℃まで３００℃／分の速度で加熱し融解させる。直ちに３００℃／分の速度で１６０℃まで冷却を行い、１６０℃で保持する。１６０℃に達した時点で時間計測を開始し、そのＤＳＣ曲線で観測される結晶化の発熱ピークトップに達した時間を半結晶化時間と定義する。
【００２１】
ここで用いられるＤＳＣ装置としては、昇温速度が３００℃／分以上、液体窒素・液体ヘリウム等を使用した冷却速度が３００℃／分以上が可能な装置であればいずれでも良く、例えば、Ｐｅｒｋｉｎ−Ｅｌｍｅｒ社製ＤＳＣユニット　ＤＳＣ７等を用いることができる。
【００２２】
結晶性のポリエステル樹脂であるポリエチレンテレフタレートは、１６０℃での半結晶化時間が５０秒程度であり、カレンダー加工は行うことができない。本発明において、非晶性ポリエステル樹脂は、カレンダー加工を可能にする観点から、半結晶化時間が５分以上の樹脂が適当であり、より好ましくは１０分以上の樹脂であり、さらに好ましくは１２時間経過しても結晶化のピークが全く認められない（以下、半結晶化時間は無限大という）ポリエステル樹脂である。
【００２３】
本発明に係わる非晶性ポリエステル樹脂は、通常のポリエステル樹脂の加工温度が２７０〜２８０℃であるのに比べて加工温度が低く、２００℃以下、好ましくは１６０〜１９０℃の条件でも加工できるものであり、加工性が良好で、カレンダー加工が可能である。尚、ここで加工温度とは、樹脂の成形可能な温度をいい、例えば、カレンダー加工法であれば、樹脂の成形可能なロール表面の温度に相当するものである。
【００２４】
非晶性ポリエステル樹脂の具体例としては、（Ａ）テレフタル酸又はその低級アルキルエステル（アルキル基の炭素数１〜３で、例えばテレフタル酸ジメチル等）（以下（Ａ）成分という）、（Ｂ）エチレングリコール（以下（Ｂ）成分という）、及び（Ｃ）テレフタル酸又はその低級アルキルエステル以外のジカルボン酸又はその低級アルキルエステル（アルキル基の炭素数１〜３）（以下（Ｃ）成分という）を共重合してなるポリエステル樹脂；（Ａ）成分、（Ｂ）成分、及び（Ｄ）エチレングリコール以外のグリコール成分（以下（Ｄ）成分という）を共重合してなるポリエステル樹脂；（Ａ）成分、（Ｂ）成分、（Ｃ）成分、及び（Ｄ）成分を共重合してなるポリエステル樹脂等が挙げられる。
【００２５】
上記（Ｃ）成分としては、芳香族ジカルボン酸、脂環族ジカルボン酸、脂肪族ジカルボン酸及びこれらの低級アルキルエステル等から選ばれる１種以上が挙げられ、芳香族ジカルボン酸としては、イソフタル酸、フタル酸、２，６−ナフタレンジカルボン酸、１，５−ナフタレンジカルボン酸、ビス（４，４’−カルボキシフェニル）メタン、アントラセンジカルボン酸、４，４’−ジフェニルエーテルジカルボン酸等が挙げられる。脂環族ジカルボン酸としては、１，４−シクロヘキサンジカルボン酸、４，４’−ジシクロヘキシルジカルボン酸等が挙げられる。脂肪族ジカルボン酸としては、アジピン酸、セバシン酸、アゼライン酸、ダイマー酸等が挙げられる。これらの（Ｃ）成分の中では、イソフタル酸及びその低級アルキルエステルが好ましい。
【００２６】
上記（Ｄ）成分としては、１，４−シクロヘキサンジメタノール、プロピレングリコール、１，５−ペンタンジオール、１，６−ヘキサンジオール、ネオペンチルグリコール、デカメチレングリコール、４，４’−ジシクロヘキシルヒドロキシメタン、４，４’−ジシクロヘキシルヒドロキシプロパン、ビスフェノールＡエチレンオキサイド付加ジオール、ポリエチレンオキサイドグリコール、ポリプロピレンオキサイドグリコール等から選ばれる１種以上が挙げられる。
【００２７】
本発明に係わる非晶性ポリエステル樹脂におけるジカルボン酸成分は、好ましくは芳香族ジカルボン酸成分が６０モル％以上であり、更に好ましくは上記（Ａ）成分が６０モル％以上である。また、グリコール成分は、好ましくは上記（Ｂ）成分が６０モル％以上である。
【００２８】
本発明に係わる非晶性ポリエステル樹脂のガラス転移温度は５０〜８５℃が好ましく、６０〜８５℃が更に好ましい。
【００２９】
本発明に係わる非晶性ポリエステル樹脂として、イーストマンケミカル社製のＴＳＵＮＡＭＩ　ＧＳ１，ＧＳ２，ＧＳ３，ＧＳ４等を用いることができる。
【００３０】
［非晶性ポリエステル樹脂組成物］
本発明の非晶性ポリエステル樹脂組成物は、上記のようなエステルを含有する本発明の可塑剤と非晶性ポリエステル樹脂とを含有する。本発明の可塑剤の含有量は、非晶性ポリエステル樹脂１００重量部に対し、柔軟性、耐ブリード性及び経済性の観点から、好ましくは１〜７０重量部、更に好ましくは３〜５０重量部、特に好ましくは５〜３０重量部である。
【００３１】
本発明の組成物は、上記以外に、滑剤等の他の成分を含有することができる。滑剤としては、ステアリン酸アミド、エチレンビス（ステアロアミド）等のアミド類、ポリエチレンワックス等の炭化水素系ワックス類、ステアリン酸等の脂肪酸類、グリセロールエステル等の脂肪酸エステル類、ステアリン酸カルシウム等の金属石鹸類、モンタン酸ワックス等のエステルワックス類、アルキルベンゼンスルホン酸塩等の芳香環を有するアニオン型界面活性剤、ポリオキシエチレンアルキルエーテル硫酸塩等のアルキレンオキサイド付加部分を有するアニオン型界面活性剤等が挙げられる。滑剤の含有量は、非晶性ポリエステル樹脂１００重量部に対し、０．０５〜３重量部が好ましく、０．１〜１．５重量部が更に好ましい。
【００３２】
本発明の組成物は、上記以外の他の成分として、帯電防止剤、防曇剤、光安定剤、紫外線吸収剤、顔料、無機充填剤、防カビ剤、抗菌剤、発泡剤、難燃剤、上記本発明の可塑剤以外の可塑剤等を、本発明の目的達成を妨げない範囲で含有することができる。
【００３３】
本発明の組成物は、加工性が良好で、例えば１６０〜１９０℃等の低温で加工することができるため、カレンダー加工も可能であり、また可塑剤の分解も起こりにくい。本発明の組成物は、フィルムやシートに成形して、各種用途に用いることができる。
【００３４】
【実施例】
実施例１〜７及び比較例１〜７
非晶性ポリエステル樹脂（ＴＳＵＮＡＭＩ　ＧＳ２；イーストマンケミカル社製、ガラス転移温度８１℃、半結晶化時間は無限大）１００重量部、ドデシルベンゼンスルホン酸ナトリウム０．８重量部、及び表２に示す種類と量の可塑剤からなる組成物を、１６５℃の６インチロールにて１５分間混練し、１９０℃のプレス成形機にて厚さ１ｍｍのテストピースを作成した。
【００３５】
尚、本発明の可塑剤（化合物１〜７）は、表１に示す（ａ）成分と（ｂ）成分とのエステルである。
【００３６】
得られたテストピースについて下記方法で柔軟性、透明性及び表面状態を評価した。また、このテストピースを手で１８０°折り曲げ、白化の有無を肉眼で観察した。更に、耐熱性を評価するために、６０℃に管理したオーブンにテストピースを入れ、１週間処理し、室温で放冷した後に、同様に柔軟性、透明性及び表面状態を評価した。これらの結果を表２に示す。
【００３７】
＜柔軟性の評価法＞
テストピースを３号ダンベルで打ち抜き、引張速度２００ｍｍ／ｍｉｎで引張試験を行い、１００％モジュラスで示した。
【００３８】
＜透明性の評価法＞
ヘイズメーターにてテストピースのヘイズ値を測定した。数字の小さい方が透明性が良好であることを示す。
【００３９】
＜表面状態（ブリードの有無）＞
熱処理前のテストピース（縦１００ｍｍ×横１００ｍｍ×厚さ１ｍｍ）については、４０℃の恒温室に１週間放置し、その表面における可塑剤のブリードの有無を肉眼で観察した。また、６０℃１週間の熱処理を行ったものについては、室温で放冷した後に、表面における可塑剤のブリードの有無を肉眼で観察した。
【００４０】
【表１】

【００４１】
【表２】

【００４２】
＊１：ＰＯＥ（４）はポリオキシエチレン４モル付加物を示す。
＊２：ネッキング現象のために測定不可
【００４３】
【発明の効果】
本発明の可塑剤は、非晶性ポリエステル樹脂の透明性を阻害させずに柔軟性を付与することができ、かつ高温で保存した時も柔軟性と透明性の変化はなく、耐熱性が良好である。また、本発明の非晶性ポリエステル樹脂組成物からなるシートやフィルムを折り曲げた時の白化を防止することもできる。[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a plasticizer for an amorphous polyester resin and an amorphous polyester resin composition having excellent flexibility, transparency and heat resistance.
[0002]
Problems to be solved by the prior art and the invention
Amorphous polyester resins having no definite melting point are used as materials for various films and sheets. This amorphous polyester resin has better processability than ordinary polyester resin and can be calendered, but has the drawback that it is easy to whiten when folded, etc., and both transparency and flexibility are satisfactory What can be done has not been obtained.
[0003]
On the other hand, as a technique for softening an amorphous polyester resin, a technique of adding a plasticizer such as an aliphatic dicarboxylic acid alkyl ether ester or a polyethylene glycol fatty acid ester has been proposed (JP-A-2000-290415 or 2001-2001). 151996). However, even if these plasticizers are added, the transparency is not satisfactory, and when high-temperature storage is assumed for the summer, the transparency and flexibility are significantly reduced, and the plasticizer is added to the sheet surface. There is a problem such as bleeding out.
[0004]
An object of the present invention is to provide a plasticizer for an amorphous polyester resin capable of imparting flexibility without impairing the transparency of the amorphous polyester resin, and an amorphous resin excellent in flexibility, transparency and heat resistance. An object of the present invention is to provide a functional polyester resin composition.
[0005]
[Means for Solving the Problems]
The present invention provides a plasticizer for an amorphous polyester resin containing an ester of the following components (a) and (b), and an amorphous polyester resin composition containing this plasticizer and an amorphous polyester resin Offer things.
(A) General formula (I)
[0006]
Embedded image

[0007]
(In the formula, n represents an integer of 2 to 6.)
A polycarbonate diol comprising a repeating structural unit represented by the following formula (hereinafter referred to as structural unit (I)), and both ends of which are hydroxyl groups.
(B) General formula (II)
[0008]
Embedded image

[0009]
(Wherein, X represents a hydrogen atom, a hydroxyl group, a linear or branched alkyl group having 1 to 22 carbon atoms, an alkenyl group or an alkoxy group, or a halogen atom; m represents an integer of 1 to 5; X may be the same or different.)
An aromatic monocarboxylic acid, a condensed polycyclic aromatic monocarboxylic acid, an alicyclic monocarboxylic acid, a hydroxy-condensed polycyclic aromatic monocarboxylic acid having one or more hydroxyl groups in a molecule, At least one selected from alicyclic monocarboxylic acids, anhydrides of these carboxylic acids, and lower alkyl esters having 1 to 3 carbon atoms.
[0010]
BEST MODE FOR CARRYING OUT THE INVENTION
[Plasticizer]
The plasticizer of the present invention contains an ester of the component (a) and the component (b) (hereinafter referred to as the ester of the present invention). As the component (a) constituting the ester of the present invention, one structural unit (I) in which n is selected from 2 to 6, preferably one structural unit (I) in which n is selected from 4 to 6 A compound containing two structural units (I) in which n is selected from 2 to 6, preferably n = 5 and 6, or a compound containing a structural unit (I) in which n = 4 and 6; A compound containing three selected structural units (I), preferably three types of structural units (I) in which n = 4, 5, and 6, and the like are mentioned. Among these, from the viewpoints of compatibility with the amorphous polyester resin and imparting flexibility, those containing the structural unit (I) of n = 4 to 6 are preferable, and two or more types of structural units having different integers n are preferable. Those containing (I) are more preferred, and those containing two or more structural units (I) selected from n = 4 to 6 are particularly preferred. When two or more structural units (I) having different integers n are included, they may be bonded in a random manner or in a block-like manner. Furthermore, from the viewpoint of compatibility with the amorphous polyester resin, the molar fraction of one structural unit (I) is preferably 85% or less, more preferably 70% or less, and particularly preferably 60% or less.
[0011]
The average molecular weight of the component (a) constituting the ester of the present invention is preferably from 400 to 3,000, more preferably from 600 to 2,500, particularly preferably from 800 to 2,000, from the viewpoint of compatibility with the amorphous polyester resin. The average molecular weight is a number average molecular weight determined from the hydroxyl value of the component (a).
[0012]
In the component (b) constituting the ester of the present invention, the aromatic monocarboxylic acid represented by the general formula (II) is benzoic acid, a hydroxyl group as a substituent, and a C 1 to C 22, preferably C 1 to C 12 carboxylic acid. Benzoic acid having 1 to 5, preferably 1 to 2 halogen atoms such as an alkyl group, an alkenyl group or an alkoxy group, or a chlorine atom or a bromine atom is exemplified. Specifically, benzoic acid, salicylic acid, p-hydroxybenzoic acid, methylbenzoic acid, n-decylbenzoic acid, isodecylbenzoic acid, 2-hydroxy-3-methylbenzoic acid, 2-hydroxy-5-methylbenzoic acid, 2 , 4-dihydroxybenzoic acid, 2,3-dihydroxybenzoic acid, 3,4,5-trihydroxybenzoic acid, 4-hydroxy-3-methoxybenzoic acid and the like. Examples of the condensed polycyclic aromatic monocarboxylic acid include α-naphthalenecarboxylic acid and β-naphthalenecarboxylic acid. Examples of the alicyclic monocarboxylic acid include cyclohexanecarboxylic acid, cyclopentanecarboxylic acid, and cycloheptanecarboxylic acid. Examples of the hydroxy-condensed polycyclic aromatic monocarboxylic acid having one or more hydroxyl groups in one molecule include 3-hydroxy-2-naphthoic acid, 1-hydroxy-2-naphthoic acid, and 1,4-dihydroxy-2-acid. Naphthoic acid and the like. Examples of the hydroxy alicyclic monocarboxylic acid include 4-hydroxycyclohexanoic acid.
[0013]
Among these components (b), benzoic acid, salicylic acid, p-hydroxybenzoic acid or lower alkyl esters thereof having 1 to 3 carbon atoms are preferable, and salicylic acid is particularly preferable from the viewpoint of heat resistance.
[0014]
The ester of the present invention can be obtained by an esterification reaction or a transesterification reaction between the component (a) and the component (b) as described above, and specific production methods include, for example, the component (a) and the component (b). The component and the organometallic catalyst such as dibutyltin oxide are used in an amount of 0.01 to 0.5% by weight based on the total charged amount of the component (a) and the component (b), and the esterification reaction is performed at 190 to 230 ° C. The method is performed by using an excess of the methyl ester of an aromatic monocarboxylic acid represented by the general formula (II), the component (b) and the component (a), and an organometallic catalyst such as dibutyltin oxide, and the component (a). And 0.01 to 0.50% by weight based on the total charged amount of the component (b) and the ester exchange reaction at 170 to 230 ° C. After the reaction, steam distillation is carried out to remove excess component (b). And the like. The ester may be a partial ester or a whole ester, and is preferably a whole ester from the viewpoint of compatibility with the resin and heat resistance.
[0015]
The ester of the present invention is a polycarbonate diol in which the component (a) contains two or more structural units (I) selected from n = 4 to 6, from the viewpoint of compatibility with the resin and heat resistance, and (b) An ester obtained from a combination in which the components are benzoic acid, salicylic acid, and p-hydroxybenzoic acid is preferable. In particular, the component (a) contains two or more structural units (I) selected from n = 4 to 6, and An ester obtained from a combination in which the molar fraction of the structural unit is 85% or less and the component (b) is salicylic acid is preferred.
[0016]
The plasticizer of the present invention may contain, in addition to the ester of the present invention, the components (a) and (b) which are unreacted components in the production of the ester of the present invention, or esters other than the ester of the present invention. .
[0017]
Esters other than the ester of the present invention include dipropylene glycol dibenzoate, ethylene glycol dibenzoate, neopentyl glycol dibenzoate, polyoxyethylene methyl ether adipate diester, and the like.
[0018]
The content of the ester of the present invention in the plasticizer of the present invention is preferably 50% by weight or more, more preferably 70% by weight or more, and further preferably 90% by weight, from the viewpoint of achieving the object of the present invention. % By weight or more.
[0019]
[Amorphous polyester resin]
In the present invention, the “amorphous polyester resin” refers to a polyester resin having a half-crystallization time of 5 minutes or more as defined below.
[0020]
<Semi-crystallization time>
First, 15 mg of a polyester resin is weighed into an aluminum pan, and heated and melted at a rate of 300 ° C./min to 300 ° C. using a differential scanning calorimeter (DSC). Immediately cool to 160 ° C. at a rate of 300 ° C./min and hold at 160 ° C. Time measurement is started when the temperature reaches 160 ° C., and the time when the exothermic peak of crystallization observed in the DSC curve is reached is defined as the half-crystallization time.
[0021]
As the DSC device used here, any device can be used as long as the temperature can be raised at a rate of 300 ° C./min or more and the cooling rate using liquid nitrogen, liquid helium, or the like can be 300 ° C./min or more. For example, Perkin -Elmer's DSC unit DSC7 or the like can be used.
[0022]
Polyethylene terephthalate, which is a crystalline polyester resin, has a half-crystallization time of about 50 seconds at 160 ° C. and cannot be calendered. In the present invention, the amorphous polyester resin is preferably a resin having a half-crystallization time of 5 minutes or more, more preferably 10 minutes or more, and still more preferably 12 minutes, from the viewpoint of enabling calendering. It is a polyester resin in which no crystallization peak is observed even after elapse of time (hereinafter, the half-crystallization time is infinite).
[0023]
The amorphous polyester resin according to the present invention has a lower processing temperature than the normal polyester resin processing temperature of 270 to 280 ° C, and can be processed even under the condition of 200 ° C or less, preferably 160 to 190 ° C. And good workability, and calendering is possible. Here, the processing temperature refers to the temperature at which the resin can be molded. For example, in the case of the calendering method, it corresponds to the temperature of the roll surface at which the resin can be molded.
[0024]
Specific examples of the amorphous polyester resin include (A) terephthalic acid or a lower alkyl ester thereof (alkyl group having 1 to 3 carbon atoms, such as dimethyl terephthalate) (hereinafter referred to as component (A)), (B) Ethylene glycol (hereinafter referred to as component (B)) and (C) dicarboxylic acid other than terephthalic acid or lower alkyl ester thereof or lower alkyl ester thereof (alkyl group having 1 to 3 carbon atoms) (hereinafter referred to as component (C)). Polyester resin obtained by copolymerizing (A) component, component (B), and (D) polyester resin obtained by copolymerizing a glycol component other than ethylene glycol (hereinafter referred to as component (D)); Examples include polyester resins obtained by copolymerizing the component (B), the component (C), and the component (D).
[0025]
Examples of the component (C) include one or more selected from aromatic dicarboxylic acids, alicyclic dicarboxylic acids, aliphatic dicarboxylic acids, and lower alkyl esters thereof. Examples of the aromatic dicarboxylic acids include isophthalic acid, Examples include phthalic acid, 2,6-naphthalenedicarboxylic acid, 1,5-naphthalenedicarboxylic acid, bis (4,4′-carboxyphenyl) methane, anthracenedicarboxylic acid, and 4,4′-diphenyletherdicarboxylic acid. Examples of the alicyclic dicarboxylic acid include 1,4-cyclohexanedicarboxylic acid and 4,4′-dicyclohexyldicarboxylic acid. Examples of the aliphatic dicarboxylic acid include adipic acid, sebacic acid, azelaic acid, and dimer acid. Among these components (C), isophthalic acid and its lower alkyl esters are preferred.
[0026]
The component (D) includes 1,4-cyclohexanedimethanol, propylene glycol, 1,5-pentanediol, 1,6-hexanediol, neopentyl glycol, decamethylene glycol, 4,4′-dicyclohexylhydroxymethane, One or more selected from 4,4'-dicyclohexylhydroxypropane, bisphenol A ethylene oxide-added diol, polyethylene oxide glycol, polypropylene oxide glycol, and the like.
[0027]
The dicarboxylic acid component in the amorphous polyester resin according to the present invention is preferably such that the aromatic dicarboxylic acid component is at least 60 mol%, more preferably the component (A) is at least 60 mol%. In the glycol component, the component (B) is preferably at least 60 mol%.
[0028]
The glass transition temperature of the amorphous polyester resin according to the present invention is preferably from 50 to 85 ° C, more preferably from 60 to 85 ° C.
[0029]
As the amorphous polyester resin according to the present invention, Tsunami GS1, GS2, GS3, GS4 and the like manufactured by Eastman Chemical Company can be used.
[0030]
[Amorphous polyester resin composition]
The amorphous polyester resin composition of the present invention contains the plasticizer of the present invention containing the above ester and the amorphous polyester resin. The content of the plasticizer of the present invention is preferably from 1 to 70 parts by weight, more preferably from 3 to 50 parts by weight, from the viewpoint of flexibility, bleed resistance and economy, based on 100 parts by weight of the amorphous polyester resin. And particularly preferably 5 to 30 parts by weight.
[0031]
The composition of the present invention can contain other components other than the above, such as a lubricant. Examples of the lubricant include amides such as stearic acid amide and ethylene bis (stearamide), hydrocarbon waxes such as polyethylene wax, fatty acids such as stearic acid, fatty acid esters such as glycerol ester, and metal soaps such as calcium stearate. , Ester waxes such as montanic acid wax, anionic surfactants having an aromatic ring such as an alkylbenzene sulfonate, and anionic surfactants having an alkylene oxide-added moiety such as polyoxyethylene alkyl ether sulfate. . The content of the lubricant is preferably 0.05 to 3 parts by weight, more preferably 0.1 to 1.5 parts by weight, based on 100 parts by weight of the amorphous polyester resin.
[0032]
The composition of the present invention includes, as components other than the above, an antistatic agent, an antifogging agent, a light stabilizer, an ultraviolet absorber, a pigment, an inorganic filler, a fungicide, an antibacterial agent, a foaming agent, a flame retardant, A plasticizer other than the above-mentioned plasticizer of the present invention can be contained within a range not to hinder the achievement of the object of the present invention.
[0033]
Since the composition of the present invention has good processability and can be processed at a low temperature of, for example, 160 to 190 ° C., it can be calendered and the plasticizer is hardly decomposed. The composition of the present invention can be formed into films and sheets and used for various applications.
[0034]
【Example】
Examples 1 to 7 and Comparative Examples 1 to 7
100 parts by weight of an amorphous polyester resin (TSUNAMI GS2; manufactured by Eastman Chemical Co., Ltd., glass transition temperature: 81 ° C., half-crystallization time: infinite); 0.8 part by weight of sodium dodecylbenzenesulfonate; And the amount of the plasticizer were kneaded with a 6-inch roll at 165 ° C. for 15 minutes, and a test piece having a thickness of 1 mm was prepared using a press forming machine at 190 ° C.
[0035]
The plasticizer (compounds 1 to 7) of the present invention is an ester of the component (a) and the component (b) shown in Table 1.
[0036]
The obtained test pieces were evaluated for flexibility, transparency and surface state by the following methods. Further, this test piece was bent by 180 ° by hand, and the presence or absence of whitening was visually observed. Furthermore, in order to evaluate the heat resistance, the test piece was placed in an oven controlled at 60 ° C., treated for one week, allowed to cool at room temperature, and then similarly evaluated for flexibility, transparency and surface state. Table 2 shows the results.
[0037]
<Flexibility evaluation method>
The test piece was punched out with a No. 3 dumbbell, and a tensile test was performed at a tensile speed of 200 mm / min, and the result was shown as 100% modulus.
[0038]
<Transparency evaluation method>
The haze value of the test piece was measured with a haze meter. Smaller numbers indicate better transparency.
[0039]
<Surface condition (with or without bleed)>
A test piece (100 mm long × 100 mm wide × 1 mm thick) before the heat treatment was left in a constant temperature room at 40 ° C. for one week, and the surface was visually observed for the presence or absence of bleeding of the plasticizer. Moreover, about what performed the heat processing of 60 degreeC for 1 week, after cooling at room temperature, the presence or absence of the bleeding of the plasticizer on the surface was visually observed.
[0040]
[Table 1]

[0041]
[Table 2]

[0042]
* 1: POE (4) indicates polyoxyethylene 4 mol adduct.
* 2: Cannot be measured due to necking phenomenon.
【The invention's effect】
The plasticizer of the present invention can impart flexibility without impairing the transparency of the amorphous polyester resin, and has no change in flexibility and transparency even when stored at a high temperature, and has good heat resistance. It is. Further, it is possible to prevent whitening when a sheet or a film made of the amorphous polyester resin composition of the present invention is bent.

Claims (6)

A plasticizer for an amorphous polyester resin containing an ester of the following components (a) and (b).
(A) General formula (I)

(In the formula, n represents an integer of 2 to 6.)
A polycarbonate diol comprising a repeating structural unit represented by the following formula (hereinafter referred to as structural unit (I)), and both ends of which are hydroxyl groups.
(B) General formula (II)

(Wherein, X represents a hydrogen atom, a hydroxyl group, a linear or branched alkyl group having 1 to 22 carbon atoms, an alkenyl group or an alkoxy group, or a halogen atom; m represents an integer of 1 to 5; X may be the same or different.)
An aromatic monocarboxylic acid, a condensed polycyclic aromatic monocarboxylic acid, an alicyclic monocarboxylic acid, a hydroxy-condensed polycyclic aromatic monocarboxylic acid having one or more hydroxyl groups in a molecule, At least one selected from alicyclic monocarboxylic acids, anhydrides of these carboxylic acids, and lower alkyl esters having 1 to 3 carbon atoms. The plasticizer according to claim 1, wherein the component (a) is a polycarbonate diol having an average molecular weight of 400 to 3000. The component (a) is a random or block polycarbonate diol containing two or more types of structural units (I) having different integers n, and the mole fraction of one type of the structural units (I) is 85% or less. 3. The plasticizer according to 1 or 2. The plasticizer according to any one of claims 1 to 3, wherein the component (b) is benzoic acid, salicylic acid, p-hydroxybenzoic acid or a lower alkyl ester thereof having 1 to 3 carbon atoms. An amorphous polyester resin composition comprising an amorphous polyester resin and the plasticizer according to claim 1. The amorphous polyester resin composition according to claim 5, wherein the content of the plasticizer is 1 to 70 parts by weight based on 100 parts by weight of the amorphous polyester resin.